Automatic Safety Device for an Umbrella

ABSTRACT

The invention is an automatic safety device for opening and closing an umbrella. The device is disposed within the grip body of an umbrella and includes a reel member, a ratchet, a coil spring, a rocker, a reset spring and a dragline. The reel member is secured to the ratchet and coil spring and is rotatably mounted about a reeling axis. When an umbrella is fully closed, the sidewall of a step-cone within a central shaft engages the releasing convex causing a pawl to disengage from the ratchet. The dragline is tied to the reel member and to the upper nest at the top of the umbrella. When closing the umbrella, the central shaft is only allowed to move downwards as restricted by the unidirectional feature of the ratchet. When the downward force is removed, the dragline holds the central shaft in position, thereby avoiding sudden deployment of the umbrella.

CROSS REFERENCE TO RELATED APPLICATIONS

This application is a continuation-in-part of co-pending International Application No. PCT/CN2009/071824 entitled Safety Structure for Automatic Opening-Closing Umbrellas with an international filing date of May 17, 2009 and further claims priority to Chinese National Application No. CN200920138367 entitled Safety Structure for Automatically Unfolding and Folding Umbrella filed May 15, 2009 which is identical to the later filed PCT application, both references incorporated herein by reference thereto.

FEDERALLY SPONSORED RESEARCH AND DEVELOPMENT

None.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an umbrella, and more particularly, to an automatic safety device for opening or closing an umbrella.

2. Background

Some umbrellas can be automatically, handily, and safely opened and closed by pressing a button with only one hand.

A typical automatic foldable umbrella is described in U.S. Pat. No. 7,461,666 entitled an Automatic Device for Opening or Closing a Multi-Folding Umbrella. As shown in FIG. 1, the automatic umbrella includes an umbrella shaft with a lower tube 11′, a middle tube 12′ with one segment or more segments, and an upper tube 13′. The lower tube 11′, middle tube 12′ and upper tube 13′ are muff-coupled. The automatic device also includes a control handle 9′ fixed on the bottom of the lower tube 11′, a raising inner tube 6′ encased in the umbrella shaft, an opening spring 7′ adapted for opening the umbrella and to slide between the exterior of the inner tube and the interior of the umbrella shaft. The automatic device further includes a dragline 8′ that is used to tense the lower nest 3′ so as to prevent it from sliding downwards when the umbrella is opened, where one end of the dragline 8′ is tied to the step-cone 81′ through the inner tube 6′. As shown in FIG. 2, the automatic device has an upper nest 2′ fixed on the top of the upper tube 13′, a lower nest 3′ sleeved glidingly on the exterior of the upper tube 13′, and a closing spring 5′ that is adapted for closing the umbrella and is tied to a rib assembly 4′ centered between the upper nest 2′ and the lower nest 3′, as further shown in FIG. 1. The other end of the dragline 8′ is tied to a dragline fixing hole defined on the top of the upper nest 2′ by circling the dragline 8′ round a set of assembly pulleys through the top of upper tub 13′, where the set of assembly pulleys are fixed on the upper nest 2′ and the lower nest 3′. In the set of assembly pulleys, two pulleys are mounted on the upper nest 2′, where one is a rewinding pulley mounted on two line-channels on the side of the top of the upper nest 2′, i.e., a notch cut on the top of the upper nest 2′, and the other is a guiding pulley placed on the inner pulley seat on the upper part of the upper nest 2′ by two line-channels, where one line-channel is positioned on the central line of the top of the upper nest 2′ and the other is located under the rewinding pulley. The set of assembly pulleys has another two pulleys, an upper rewinding pulley and a lower rewinding pulley, mounted on the side of the lower nest 3′, where their channels are all on the lateral side of the lower nest 3′. As further shown in FIG. 2, a bushing 911′ in the lower part of the handle body 91′ of the control handle 91′ is spliced with the lower tube 11′ and secured with a pin. A button hole is cut on the sidewall of the upper part of the handle body 91′. A button 92′ with a reset spring 925′ and a snap convex 924′ is received in the button hole. The rocker 93′ having a push spring 935′ and connected with the handle body 91′ from the underneath of the button hole is adapted for locking and/or releasing the step-cone 81′ that is connected to the end of the dragline 8′. The movable ring 94′ with the lifting spring 942′ is located below a button-guide groove 913′ in a cavity 912′ defined in the handle body 91′ and around the upper part of the rocker 93′ and the lower part of the lower tube, where the lifting spring 942′ is pre-compressed under the movable ring 94′.

After the umbrella is closed and the shaft is in the state of compression, the snap convex 924′ of the button 92′ falls into the locking recess 131′ on the lower part of the upper tube 13′, therefore, the upper tube 13′ is locked to maintain the shaft in the state of compression, when the movable ring 494′ is forced downwards by the bottom of the middle tube 12′ and staggers with the button 92′ but the rocker 93′ still locks the step-cone 81′ tied to the dragline 8′.

When the button 92′ is pressed for the first time, it moves inwards but does not touch the rocker 93′ because the movable ring 94′ staggers with the button 92′, the snap convex 924′ departs from the locking recess 131′ on the lower part of the upper tube 13′, namely, the shaft is not locked and the umbrella is unfurled under the action of the spring for opening 7′, the step-cone 81′ is still locked by the rocker 93′ so as to strain the dragline 8′ to prevent the lower nest 3′ from sliding downwards; but the movable ring 94′ moves upwards to the position that the button 92′ can touch under the action of the lifting spring 942′.

When the button 92′ is pressed again, it will push the movable ring 94′ inwards, which drives the rocker 93′ to rotate, consequently, the step-cone 81′ is released, the lower nest 3′ slides downwards for the loss of support and the spring for closing 5′ pulls the rib assembly 4′ to push the lower nest 3′ downwards back to roll up the umbrella. By this time, the shaft is still in an unfolded state. To completely close the umbrella, a pressing force is needed to apply to the top of the umbrella towards the handle such that the shaft displaces from the extended position to the folded position while the spring for opening 7′ accumulates a restoring force for action and the control unit disposed within the handle regains its control over the shaft and the step-cone 81′. Thus, the umbrella is in a fully-folded state.

The working principles of other automatic foldable umbrellas similar to U.S. Pat. No. 7,461,666 are described in Chinese Patent Application Nos. 01217730, 01237609, 01262761, and 03267824. The main difference between the device in U.S. Pat. No. 7,461,666 and the devices in the Chinese references is the configuration of the control unit within the handle, which controls the umbrella shaft and a step-cone.

Although an automatic foldable umbrella is easy to use, such devices include hidden dangers. When pushing down the central shaft for folding, the user must apply a relatively large force to the central shaft to overcome a biasing force by the opening spring. If the user inadvertently allows the umbrella to slip from his/her grasp during pushing, the central shaft may bounce back to extend and the rib may spread instantly, which could result in damage to the umbrella and injury to the user and other persons nearby. Therefore, what is required in the field of umbrellas is a solution to the problem of shaft rebound before full compression is achieved.

SUMMARY OF THE INVENTION

The present invention provides an automatic safety device for opening or closing umbrella which prevents unexpected shaft rebounding and umbrella opening during folding.

To solve the above-said problem, the present invention includes an automatic safety device for opening or closing umbrella, which is disposed within the grip body of an umbrella. The safety device includes a reel member, a ratchet, a coil spring, a rocker, a reset spring, and a dragline. In a rotational manner, the two ends of the reel member are respectively mounted into the shaft holes on the two lower sidewalls of a grip body about a reeling axis. The reel member has one side coupled with the ratchet and the other side coupled with the inner end of the coil spring. One end of the dragline is tied to the reel member and the other end is tied to the upper nest on the top of the umbrella. The ratchet includes a plurality of ratchet teeth, and the outer end of the coil spring is secured to the grip body. One end of the rocker is pivotally mounted in the grip body about a pivot axis and the other end is a pawl. By virtue of a biasing force by the reset spring, the pawl and the ratchet teeth engage with or disengage from each other to form an unidirectional intermittent motion mechanism. A releasing convex is mounted on the interior wall of the rocker. The releasing convex, passing through an opening on the sidewall of the grip body, further extends into the shaft hole of the grip body. When an umbrella is in a fully closed state, the sidewall of the step-cone within the lower tube of the central shaft pushes the releasing convex, causing the pawl to disengage from the ratchet teeth so as to release the unidirectional intermittent motion mechanism.

The reset spring is disposed between the exterior wall of the rocker and the interior wall of the grip shell along the grip. The reset spring applies an urging force onto the rocker so that the pawl is engaged with the ratchet teeth of the ratchet.

The step-cone has an opening, through which the upper end of the dragline extends to the upper nest on the top of the umbrella and is fastened thereto.

As the result of the present invention, the safety problem associated with automatic foldable umbrellas is successfully solved. When it is desired to close the umbrella, the central shaft is pushed downwards during folding, the reel member is rotated in the counterclockwise direction by the strength of the restoring force of the coil spring to reel in the dragline. In the event the downward force applied to the umbrella is suddenly removed, the dragline tends to pull the reel member in the clockwise direction, and then, the free end of the rocker is engaged with one of the ratchet teeth to guard against clockwise rotation so as to hold the upper nest in position. Therefore, by using the unidirectional function of the ratchet, the safety device successfully prevents undesirable opening of the umbrella and avoids unexpected injury to the user and persons nearby.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in more detail, by way of example only, with reference to the accompanying drawings.

FIG. 1 is a sectional view of a conventional automatic foldable umbrella from the prior art.

FIG. 2 is a cross sectional view of the control handle shown in FIG. 1.

FIG. 3 is an exploded perspective view showing the automatic safety device for opening or closing an umbrella in accordance with an embodiment of the present invention.

FIG. 4 is a sectional view showing the automatic safety device during folding in accordance with an embodiment of the present invention.

FIG. 5 is a sectional view showing the automatic safety device in a fully closed state in accordance with an embodiment of the present invention.

FIG. 6 is a sectional view showing the automatic safety device in an open state in accordance with an embodiment of the present invention.

FIG. 7 is a sectional view showing a preferred embodiment of the automatic safety device in accordance with an embodiment of the present invention.

FIG. 8 is an exploded perspective view showing a grip with the automatic safety device in accordance with an embodiment of the present invention.

DETAILED DESCRIPTION OF THE INVENTION

Embodiments of the present invention are described in conjunction with the accompanying drawings.

The invention is an automatic safety device for opening or closing an umbrella. The automatic safety device is disposed within the lower part of the grip body of an umbrella, interconnecting the control unit and the upper nest of the umbrella.

Referring now to FIGS. 3 and 4, the automatic safety device is disposed within the grip body 2 of the grip 11 including a reel member 3, a ratchet 4, a coil spring 5, a rocker 6, a reset spring 7 and a dragline 8.

The control unit is disposed within the upper part of the grip body 2 of the grip 11. Since the control unit is not the emphasis for protection according to this invention, the illustration of the control unit is omitted in FIGS. 3-6 so as to focus attention upon the automatic safety device. The grip body 2 has a shaft hole for mounting the lower tube 12 of the central shaft. The step-cone 9 is positioned within the lower tube 12 of the central shaft. The two ends of the reel member 3 are respectively mounted into the shaft holes on the two lower sidewalls of the grip body 2 about a reeling axis. The reel member 3 has one side coupled with the ratchet 4 and the other side coupled with the inner end of the coil spring 5. The outer end of the coil spring 5 is secured to the grip body 2. The ratchet 4 includes a plurality of ratchet teeth 41. The coil spring 5 functions to bias the reel member towards rotation. The dragline 8 has one end tied to the reel member 3 and the other end tied to the upper nest 14 at the top of the umbrella, the latter feature not shown in FIGS. 3-6. To guard against displacement of the dragline 8, the step-cone 9 has an opening 91, through which the upper end of the dragline 8 extends to the upper nest 14 at the top of the umbrella and is fastened thereto.

The rocker 6 has one end pivotally mounted in the grip body 2 about a pivot axis, and the other free end is a pawl 61. The reset spring 7 is disposed between the exterior wall of the rocker 6 and the interior wall of the grip shell 111 of the grip 11. The reset spring 7 applies an urging force onto the rocker 6 so that the pawl 61 is engaged with the ratchet teeth 41 of the ratchet 4. The ratchet 4, rocker 6 and reset spring 7 work together to form an unidirectional intermittent motion mechanism. A releasing convex 62 is mounted on the interior wall of the rocker 6. The releasing convex 62, passing through an opening 22 on the sidewall of the grip body 2, further extends into the shaft hole 21 of the grip body 2. When an umbrella is in a fully closed state, the sidewall of the step-cone 9 within the lower tube 12 of the central shaft pushes the releasing convex 62, positioning the pawl 61 for opening or closing umbrella.

Referring now to FIG. 7, a preferred embodiment of the automatic safety device is shown including a central shaft 20 with a lower tube 12, a middle tube having one segment or more segments, and an upper tube 18, a lower nest 19, a upper nest 14, and a rib assembly 15 that are disposed on the upper tube 18, an umbrella grip 11 that is fixed on the bottom of the lower tube 12. The central shaft has within itself an opening spring 16 and a main dragline 8′ that is used to tense the lower nest 19 so as to prevent it from sliding downwards when the umbrella is opened. The umbrella grip 11 has within itself a control unit that controls the automatic opening and closing of the umbrella and a safety device according to the present invention. The central shaft 20, the rib assembly 15, and control unit shown in FIG. 7 are exactly the same as those of the conventional umbrella shown in FIG. 1. However, unlike the device in FIG. 1, the automatic safety device of the present invention is disposed within the lower part of the umbrella handle.

Referring now to FIG. 8, the umbrella grip 11 includes a grip body 2 and a grip shell 111. The grip body 2 has a hole 21 for fixing the bottom of the lower tube 12. On the sidewall of the upper part of the grip shell 111, a hole is cut for mounting the control button 18. A control unit, which is triggered by the control button 18, is disposed within the upper part of the grip body 2 to control opening or closing of the umbrella. The automatic safety device is disposed in the lower chamber of the grip body 2. Two draglines pass through the opening of the step-cone 9. One is the main dragline 8′ that is used to tense the lower nest 19 so as to prevent it from sliding downwards when the umbrella is opened. The other is the dragline 8 is an integral part of the safety device according to the present invention. The two ends of the main dragline 8′ are respectively fastened to the lower nest 19 and the step-cone 9. The two ends of the dragline 8 are respectively fastened to the reel member 3 and the upper nest 14.

Functionality of the safety device includes the following. When the rib assembly is moved from a spread position to a collapsed position, the step-cone 9 is brought to the upper part of the central shaft 20. As the central shaft is further pushed downwards to be folded telescopically, the reel member 3 keeps turning and reeling in the dragline 8 via the coil spring 5, as represented in FIG. 3. However, once the force pushing the central shaft 20 downwards is removed, the dragline 8 tends to pull the reel member 3 in the counter direction, then the pawl 61 of the rocker 6 engages the ratchet teeth 41 along the ratchet 4 to guard against such rotation causing the dragline 8 to tense the upper nest 14 in position preventing unexpected deployment of the umbrella and avoiding injury to nearby persons.

When the central shaft 20 is completely folded and the rib assembly is in a collapsed state, the step-cone 9 is brought back to position within the grip 11 as shown in FIG. 4, and is under the control of the control unit (the latter omitted as it is not the focus of this invention). Then, the step-cone 9 comes into contact with the releasing convex 62, pushing the rocker 6 outwards, thereby, disengaging the pawl 61 of the rocker 6 from the ratchet teeth 41 of the ratchet 4. The dragline 8 is reeled in by the reel member 3. When it is desired to open the umbrella, since the rocker 6 being pushed outwards by the step-cone 9 is disengaged from the ratchet teeth 41, the dragline 8 can extend freely without any restrictions from the ratchet 6. The umbrella is opened smoothly as shown in FIG. 5.

Other than the aforesaid mechanism of using the step-cone, rocker and ratchet, the present invention can also use other control means to release restriction on the rotation of the ratchet by the rocker. 

What is claimed is:
 1. An automatic safety device disposed within a grip body of an umbrella for opening and closing said umbrella comprising: a reel member; a ratchet; a coil spring; a rocker; a reset spring; and a dragline; whereby said reel member includes a pair of ends, each said end separately mounted into a hole along a sidewall of said grip body about a reeling axis, said reel member being rotatable with respect to said grip body; said reel member has a first side coupled to said ratchet and a second side coupled with an inner end of said coil spring; a first end of said dragline tied to said reel member and a second end tied to an upper nest at a top end of said umbrella; said ratchet has a plurality of ratchet teeth; an outer end of said coil spring secured to said grip body; one end of said rocker pivotally mounted to said grip body about a pivot axis and another end of said rocker includes a pawl; said pawl and said ratchet teeth engage with or disengage from each other to form a unidirectional intermittent motion mechanism by virtue of a biasing force from said reset spring; a releasing convex mounted on an interior wall of said rocker; said releasing convex passing through an opening along said sidewall of said grip body and further extending into a shaft hole along said grip body; when said umbrella is fully closed, a step-cone within a lower tube of a central shaft contacts said releasing convex disengaging said pawl from said ratchet teeth.
 2. The automatic safety device of claim 1 whereby said reset spring is disposed between an exterior side of said rocker and an interior side of said grip, said reset spring applies an urging force onto said rocker so that said pawl engages said ratchet teeth.
 3. The automatic safety device of claim 1 whereby said step-cone has an opening through which an upper end of the said dragline extends to said upper nest at said top end of said umbrella and is fastened there to. 